Apparatus for drilling wells



April 1 1, 1961 J. A. REID APPARATUS FOR DRILLING wELLs 4 sheets-sheet 1Original Filed Sept. 20, 1954 illilllllllf'.

4 Sheets-Sheet 2 J. A. REID APPARATUS FOR DRILLING WELLS April l1, 1961Original Filed Sept. 20, 1954 Aprll 11, 1961 J. A. REID APPARATUS FORDRILLING WELLS Original Filed Sept. 20, 1954 4 Sheets-Shet 5 April 11,1961 1 A RE|D 2,979,142

APPARATUS FoR DRILLING WELLS original Filed sept. 2o, 1954 4Sheets-Sheet 4 INEN TOR. By dem www W APPARATUS non DRiLLlNG WELLS JamesA. Reid, Bartlesville, Okla., assignor to Phillips Petroleum Company, acorporation of Delaware Y Original application Sept. 20, 1954, Ser. No.456,911, now Patent No. 2,825,534, dated Mar. 4, 1958. Divided and thisapplication July 3, 1957, Ser. No. 669,763

4 Claims. (Cl. 175--105) This invention relates to apparatus fordrilling wells. In another aspect, it relates to a drill bit of improvedconstruction.

This application is a division of Serial No. 456,911, tiled September20, 1954, now U.S. Patent No. 2,825,534.

Heretofore, oil or gas wells have ordinarily been drilled in the earthby a rotary drill or by cable tools. ln both of these drilling systems,a string of drill pipe has been used which extends from the drillingtool to the surface of the earth. In the case of rotary drills, thisdrill string transfers torque from a prime mover at the surface of theearth to the drilling tool at the bottom of the well. In drilling withcable tools, the drill string carries drilling mud to the bottom of thewell, and devices have been proposed, depending upon friction betweenthe drilling tool and drill string, to cause rotation of the bit as thedrilling progresses. Such rotation of the bit is quite important toobtain a proper drilling action.

It will be evident that the use of such a string of drill pipe greatlyincreases the cost of the drilling operation. First, the cost of thepipe is a factor and, second, it is dicult and costly to remove a longstring of pipe to repair or replace the bit. Where a drill-rotatingdevice is attached to the drill string, it s necessary to provide adevice for preventing reverse rotation of the drill string relative tothe drill hole.

In accordance with this invention, l obtain rotation of the bit withoututilizing a drill string by securing a rotator device to the drillingtool, for example, to the drill stem or drill bit. This device engagesthe formations defining the drill hole in such fashion as to cause aunidirectional rotation of the drilling tool. In this manner, part ofthe reciprocatory or vibrational energy applied to the drill bit is usedto effect rotation thereof.

This permits a downhole prime mover to be used, which can advantageouslybe of the electromagnetic or magnetostrictive type, so that the drillstring can be eliminated and the complete drilling apparatus suspendedby a cable or conduit for carrying drilling fluid to the drilling area.Thus, the drilling tool can be removed merely by reeling in the cable orconduit without removing and disassembling a long strip of drill pipe.Although the most advantageous applications of the present invention areto systems utilizing a downhole magnetostrctive or electromagnetic primemover, it will be evident that, in some cases, the motive power can besupplied from the surface of the earth and transmitted through a cableto the drilling tool.

Accordingly, it is an object of the invention to provide well drillingapparatus or" improved construction.

. It is a further object to provide apparatus for obtaining rotation ofthe drill bit without the use of a drill string.

Itis a still further object to provide a system where the prime movercan be located downhole with the drilling tool and suspended by a cableor flexible conduit.

Various other objects, advantages and features of the invention willbecome apparent from the following de- I 2,979,142 Patented Apr. ll,'i961 tailed description taken in conjunction with the accompanyingdrawings, in which:

Figure 1 is a vertical elevational view, partially in section, of adrilling tool constructed in accordance with the invention;

Figure 2. is a vertical sectional view, partially in elevation, of aswivel unit;

Figure 3 is a perspective view of a drill bit constructed in accordancewith the invention;

Figure 4 is a sectional View taken along the line 4 4 of Figure 3,looking in the direction of the arrows;

Figure 5 is a vertical elevational view of a modied form of drillingtool;

Figure 6 is a vertical sectional View, partially in elevation, of anelectromagnetic prime mover;

Figure 7 is an enlarged vertical sectional view partially in elevation,of a bit rotator device; and

Figure 8 is a sectional view taken along the lines 3--8 of Figure 7,looking in the direction of the arrows.

Referring now to Figures 1 to 4, inclusive, I have shown an elongateddrilling tool 10 comprising a cylindrical drill stem 11 and a bit 12.Mounted within the drill stem 111 and protruding upwardly therefrom is aniagnetostrictive driving unit or motor 13 which is secured by a swivelconnection 14 to a ilexible conduit or cable 15.

When actuated in the manner hereinafter explained, the prime moverproduces a vibratory movement of the drill bit.

Referring to Figures 3 and 4, it will be noted that the drill bit has aseries of teeth 12T and openings 16, the teeth being defined by a seriesof at surfaces 17 which are inclined at a small angle with respect to aplane perpendicular to the axis of the tool. Certain of the surfaces 17have a recess 13, and a spring element 19, preferably formed from steel,has one end 19a thereof secured within each recess 18, as by a bolt 20,and its other end 19b protruding beyond the face of the associated ilatsurfaces i7.

As the bit descends and contacts the formation at the bottom of the wellin its drilling action, it will be evident that the strips or elements19 are pushed inwardly toward the face of the drill bit and thereuponexert a force upon the drill bit tending to rotate it in acounterclockwise direction, as viewed in Figure 3. These elements, ofcourse, exert no force tending to rotate the drill bit in the oppositedirection and, hence, can be referred to as devices secured to the drillbit and engageable with the vadjoining formation to cause rotation ofthe drill bit in one direction but not in the other direction.

As shown and preferably, the motor which provides the aforementionedvibratory drilling action is located at the bottom of the hole and formsa part of the drilling tool. In the embodiment shown, this prime moverincludes an annular coil 22 mounted concentrically within the, drillstem 11. Mounted within the coil is an annular core formed from a seriesof vertical strips or laminations 23 of magnetostrictive material whichare attached, atthe lower end thereof, to the drill bit 12 by a pair ofheavy metal plates 23a, 23b and, at the upper end thereof,` to a pair ofheavy metal plates 24 and 25. An annular sealing device 26 is disposedat the top of the laminated core defined by the strips 23 ofmagnetostrictive material. These strips are arranged to define a'central passage .2y-7 communicating with the openings 16, Figure 3, inYthe drill bit for the purpose of supplying drilling fluid thereto. Whenthe coil 22, Figure 1, is energized' by alternating current of properfrequency, the magnetostrictive elements vibrate and impart a vibratorymovement to the drill bit 12 in the form of rapid and repetitive powerimpulses.

'Ihe swivel 14 includes an adapter 30 bolted to the plates 24, 25 andsecured to a housing 31 by mechanism including roller bearings 32, 33and a rotary seal 3-4. This structure permits the drilling tool torotate freely relative to the housing 3 1 which is suitably connened tothe cable or hose 15, Figure l. The entire unit is of suliicient weightto permit proper operation of the drill bit.

Current is supplied to the coil 22 by two leads 35 and 36 which extendthrough sets 37' and 33 of slip rings and additional conductors, one ofwhich is indicated at 39, to the surface.

In operation, a drilling fluid is supplied to the bit through the hose15, Figure l, a passage 40 extending through housing 3l, and the passage27 to the openings 16 in the drill bit.- At the same time, current issupplied to the coil 22 through leads 35 and 3d at the frequency ofresonance of the mechanical system consisting of the magnetostrictiveelements 23, the drill stem, the drill bit and the parts Securedthereto. This produces a vibratory drilling movement of the drill bit12. Each time the drill bit moves downward in the course of thisvibratory movement, a force is applied thereto by the spring elements 19tending to rotate it in a counterclockwise direction, Figure 3. Thisunidirectional force causes the drill to rotate with the result that thedrilling is conducted in a rapid and ecient manner, and the teeth of thebit contact different parts of the hole as the drilling progresses. Ifdesired, the spring elements can be arranged to rotate the bit in theopposite direction, i.e., clockwise, as viewed in Figure 3.

It will be evident that the described structure achieves the advantagesof the invention in providing a system for operating the drill bitwithout the provision of a string of drill pipe, rotation of the bit inan etlicient and controlled manner 'being obtained by the engagement ofthe spring elements 19 with the formation at the bottom of the hole.When it is necessary to repair or replace the bit or prime movermechanism, the drilling tool can be readily raised to the surface merelyby reeling in the cable 15.

In Figures to 8, inclusive, I have shown a modified -form of theinvention wherein the bit-rotating device is secured to the drill stemrather than the drill bit, and the power is suppliedelectromagnetically. In -this modiiication, there is an elongateddrilling tool including a cylindrical stem 45 carrying a conventionaldrill bit 46, a reciprocatory movement being applied to the stem 45 andbit 46 by an electromagnetic motor 47 which, in turn, is suspended froma length 48 of pipe attached to the end of a flexible hose or cable 49.

Secured to the drill stem 45 or, if desired, to the motor casing is abit-rotating device 50 having a housing 51 provided with arcuate slots52 in which are mounted, respectively, a plurality of outwardlyprotruding curved blocks or ribs 53. These ribs are urged outwardly intoengagement with the adjoining formation by springs 54, and each rib isprovided with an enlarged inner end portion 55 for the purpose ofretaining it within the slot 52'.

A cylindrical sleeve 56 is fixed to the outer surface of the drill stem45 and is rotatably mounted with respect to the housing 51 by rollerbearings 57 and 58. At the upper end thereof, the interior of thehousing 51 is shaped to form a plurality of ratchet teeth 60 with whichcoact a pair of pawls 61. Each pawl is pivotally mounted within a recess62 formed within the sleeve 56, and urged to an extended position by aspring 63.

As the drill stem 4S moves upwardly and downwardly in a reciprocatorymanner, this movement is transmitted to the housing 51 which rotatesback and `forth as it is raised and lowered due to the engagement of theribs 53 With the formations dening the wall of the well. During thedownstroke, the housing 51 rotates in a clockwise direction, Figure 8,with the result that two of the teeth `60 engage the pawls 61 and imparta rotary movement to the sleeve 56 and the drill stem 45 securedthereto. During the up'stroke, however, the housing 51 rotates in acounterclockwise direction, Figure 8, and Vthe pawls 61 slip past theteeth 60 without producing any rotation of the drill stern and drillbit.Accordingly, the bitrotating device causes rotation of the drill stemand drill bit during the downstroke but not during the upstroke.

The aforementioned reciprocating movement is imparted to the drill sternby the electromagnetic motor 47, Figure `6, which is mounted within acylindrical casing 70. A bushing ia holds coil 71 within the casing. Thecoil is waterproofed by being sealed within an elastomeric insulatorenclosed within a non-magnetic, corrosion proof material such as copper,Monel, or stainless steel. Within the coil is a movable hollowcylindrical armature 72. The armature is urged upwardly by a spring 73.The drill stem 45. is attached to the lower end of the armature and theinterior passage of the drill stem communicates with an internal passage72a in the armature and with the interior passage in pipe 48. Current issupplied to the coil by two leads 74- and 75, lead 74 extending to thesurface through slip ring and contact sets 76, 77 and lead 75 extendingto the surface through slip ring and contact sets 76 and 79.

ln operation, the drilling tool is lowered into the well and drillinglluid is circulated to the bit through the interior passages in pipe 48,armature 72 and drill stem 45. Pulses of direct current are supplied tothe coil 71 through leads 74, 7S and, at each energization of the coil,the armature 72 is moved downwardly against the force of spring 73 thuscausing a downward movement of the drill stem and bit to provide aneffective drilling action. During the downward progress of the bit, itis rotated by the device 5d in the manner already explained.

When the current flow to the coil is stopped, spring 73 causes thearmature, drill stem and drill bit to move upwardly without rotatingdue, again, to the described action of the device S0. Consequently, thewell is drilled by reciprocating movement of the bit with rotationthereof during each downstroke. Here again, the prime mover supplyingthe mechanical energy to the bit is located downhole, and the use of along drill string is eliminated `so that the drilling tool can be raisedto the surface merely by reeling in the cable, without lifting anddisassembling a long string of drill pipe.

While the invention has been described in connection with present,preferred embodiments thereof, it is to be understood that lthisdescription is illustrative only and is not intended to limit theinvention.

I claim:

l. Apparatus for drilling a well which comprises, in combination, adrilling tool including an elongated drill stem, a motor connected tothe upper end of said drill stem, and a bit connected to the lower endof said drill stem, means for suspending said tool in a well, means foractuating said motor to apply repetitive reciprocat'ory power impulsesthrough said stem to said bit and thereby producea drilling action, anda device secured to said drill stem and having a member engageable withthe walls of said well, said device including a housing rotatablymounted and fixed longitudinally and concentrically with said stem, aseries of curved ribs protruding outwardly from said housing and deninghelices therearound, means engaging said ribs and said housing forurging said ribs into engagement with the walls of said well, saidhousing having a series of ratchet teeth formed interiorly thereof in aplane perpendicular to the axis of the drill stem, and a plurality ofratchet pawls pivotally secured to said drill stem and engageable withsaid ratchet teeth to cause rotation of the drill stem with said devicein one direction and not in the opposite direction.

2L Apparatus for drilling a well which comprises, in combination, anelongated tubular casing, a flexible conduit secured to the top of saidcasing and adapted to suspend said casing in a well, a cylindrical coilmounted interiorly of said casing, a tubular armature, means forsupporting said armature for reciprocating movement within said coil, ahollow drill stem secured to said armature and extending downwardlytherefrom, a drill bit secured to the lower end of said stem, means forcirculating drilling iluid downwardly through said conduit, saidarmature and said drill stem to said drill bit, means for applyingelectrical energy to said coil to effect reciprocatory movement of saidarmature and said drill bit, and a device secured to said drill stern,said device including a housing mounted rotatable and iXedlongitudinally and concentrically on said stem, a series of curved ribsprotruding outwardly from said housing and defining helices thereabout,means engaging said housing and said ribs for urging said ribs intoengagement with the walls of said wall, said housing having a series ofratchet teeth formed interiorly thereof in a plane perpendicular to theaxis of the drill stem, and a plurality of ratchet pawls pivotallysecured to said drill stem and engageable with said ratchet teeth tocause rotation of the drill stem with said device in one direction butnot in the opposite direction.

3. Apparatus for drilling a well which comprises, in combination, adrilling tool including an elongated drill stem, and a bit connected tothe lower end of said drill stem; means for suspending said tool in awell; means connected to the upper end of said drill stem for applyingrepetitive reciprocatory power impulses through said drill stem to saidbit and thereby produce a drilling action; and a device rotatablymounted and iixed longitudinally on said drill stem, said deviceincluding a housing, a plurality o'f rib members mounted on saidhousing, each of said rib members defining a portion of a helix aboutsaid device and comprising a means for engaging the walls of the well,springs engaging said housing and said members urging said members intoengagement with the walls of the well, and ratchet means connectedbetween said device and said drill stem for effecting rotation of thehousing in unison with the drill stem when the latter is movedlongitudinally with the bit in one direction, but not when the drillstem is moved longitudinally with the bit in the opposite direction.

4. Apparatus for drilling a well which comprises, in combination, adrilling tool including an elongated drill stem, and a bit connected tothe lower end of said drill stem; means for suspending said tool in awell; means connected to the upper end of said stem for longitudinallyvibrating said stem to apply repetitive reciprocal power impulses tosaid bit and thereby produce a drilling action; a device rotatablysupported from said drill stem and having a plurality of helical ribmembers engageable with the walls of the well, and means for urging saidhelical members into engagement with the walls of the well; and means,disposed between said stem and said device for connecting said stem tosaid device lfor rotation in unison therewith in a rst rotary directionresponsive to said stem moving in a tirst reciprocal direction when saidrib members are engaged with the walls of the well and for disconnectingsaid stem ifrom said device responsive to relative rotation of saiddevice on said stem in response to said stem moving in a secondreciprocal direction.

References Cited in the le of this patent UNITED STATES PATENTS 47,599Lovegrove May 2, 1865 1,331,103 Gildea Feb. 17, 1920 1,430,473 StollSept. 26, 1922 1,639,242 Versteeg Aug. 16, 192.7 1,767,286 HinderliterJune 24, 1930 1,769,921 Hansen July 8, 1930 1,899,438 Grant Feb. 28,1933 2,589,534 Buttolph 1 Mar. 18, 1952 2,672,322 Bodine Mar. 16, 19542,712,434 Giles et al. July 5, 1955 2,728,556 House Dec. 27, 1955FOREIGN PATENTS 2,443 Great Britain Jan. 26, 1905 UNITED STATES FATENTOFFICE CERTIFICATE 0F CORREGTIQN Patent No., 2979vl42 April llIk 1961James A. Reid lt is hereby certified that error appears in the abovenumbered patent requiring correction and that the Said Letters Patent.should read as corrected below Signed and sealed this 24th dayof-October 1961o (SEAL) Attest: l

ERNEST W. SWIDER ADAVID L. LADD Attesting Officer I Commissioner ofPatents USCOMM-DCv

